Is it possible to convert a string to byte array and then convert it back to the original string in Java or Android?
My objective is to send some strings to a microcontroller (Arduino) and store it into EEPROM (which is only 1 KB). I tried to use an MD5 hash, but it seems it's only a one way encryption. What can I do to deal with this issue?
Use [String.getBytes()][1]
to convert to bytes and use [String(byte[] data)][2]
constructor to convert back to string.
import java.io.FileInputStream; import java.io.ByteArrayOutputStream;
public class FileHashStream { // write a new method that will provide a new Byte array, and where this generally reads from an input stream
public static byte[] read(InputStream is) throws Exception
{
String path = /* type in the absolute path for the 'commons-codec-1.10-bin.zip' */;
// must need a Byte buffer
byte[] buf = new byte[1024 * 16]
// we will use 16 kilobytes
int len = 0;
// we need a new input stream
FileInputStream is = new FileInputStream(path);
// use the buffer to update our "MessageDigest" instance
while(true)
{
len = is.read(buf);
if(len < 0) break;
md.update(buf, 0, len);
}
// close the input stream
is.close();
// call the "digest" method for obtaining the final hash-result
byte[] ret = md.digest();
System.out.println("Length of Hash: " + ret.length);
for(byte b : ret)
{
System.out.println(b + ", ");
}
String compare = "49276d206b696c6c696e6720796f757220627261696e206c696b65206120706f69736f6e6f7573206d757368726f6f6d";
String verification = Hex.encodeHexString(ret);
System.out.println();
System.out.println("===")
System.out.println(verification);
System.out.println("Equals? " + verification.equals(compare));
}
}
You can do it like this.
String to byte array
String stringToConvert = "This String is 76 characters long and will be converted to an array of bytes";
byte[] theByteArray = stringToConvert.getBytes();
http://www.javadb.com/convert-string-to-byte-array
Byte array to String
byte[] byteArray = new byte[] {87, 79, 87, 46, 46, 46};
String value = new String(byteArray);
Source: Stackoverflow.com